Neito has short, slick blond hair, parted to the right on his forehead. He has grey eyes with white pupils.
His Hero costume is a tuxedo with several clocks around his waist, presumably to help him keep track of time when using his Quirk. He leaves his collar upturned, and wears a dotted tie.
Neito is shown to be calm, collected, and intelligent. Among Class-B's students, he's the most fervent about wanting to topple Class-A's popularity. He is also disagreeable, sarcastic, and vocal. He seems to be jealous of Class-A's popularity, but also worries that the fact that they are always getting into trouble will get the rest of the school in trouble too. When he hears that Class-A fails in some way, he will usually laugh out loud and passive-aggressively ask how it's impossible for them to fail since they are meant to be the superior class.
He is shown to have somewhat of an inferiority complex, as he takes whatever opportunities he can get to mock and challenge, one up and surpass anyone in Class 1-A. This even extends to mocking himself in order to mock the students in 1-A who had to take remedial lessons during the School Trip Arc, despite he himself being the only one from class 1-B having to also take remedial lessons. He's been quoted by people as being mentally unstable, but this is more than likely a joke regarding his obsession with overtaking class 1-A.
In spite of his bitterness and overconfidence, he does seem to feel threatened and intimidated by class 1-A for their skills and strength, as seen when he sighed in relief when he learned that he would not have to face them in order to gain a provisional license.
Neito Monoma first appears at the opening ceremony for the U.A. Sports Festival. He takes the field with his fellow classmates in Class 1-B.He is able to qualify for the Cavalry Battle after taking thirty-sixth place in the Obstacle Race. 
While forming teams for the Cavalry Battle, Neito gives a small speech to his peers. He says that all the fans are too focused on Class 1-A just because they faught a few villains. He believes Class 1-B isn't second rate and tells his fellows to step their game up and show Class 1-A what they can do. Neito forms his team with Kosei Tsuburaba, Sen Kaibara, and Shihai Kuroiro.Just before the Cavalry Battle begins, Neito tells Tetsutetsu there are no hard feelings between their teams. Soon after the round begins, Neito is able to steal Toru Hagakure with ease. He follows up by stealing the headband of Katsuki Bakugo. After stealing Katsuki's headband, Neito takes a moment to explain his strategy from the Obstacle Race.
Neito explains that he and some of his classmates threw the Obstacle Race in order to scout Class 1-A's Quirks. They remained in the top forty while Katsuki and their other rivals used their Quirk's freely. Neito comments that it was foolish on their part to obsess about the preliminary round and continues to taunt Katsuki. Neito talks about how Katsuki is famous for being involved in the Sludge Villain incident and calls him a victim. Now furious, Katsuki promises to eliminate Neito's team. Kosei pleads for Neito to stop provoking Katsuki, which Neito apologizes for because it's unheroic of him. Even so, Neito says Katsuki is like a moronic villain desperate for revenge. Greatly irritated, Katsuki attacks, but Neito evades and counters using Katsuki's own explosion on him. Then Neito quickly touches Eijiro Kirishima and uses his hardening Quirk to block the subsequent strike. Katsuki then realizes Neito's Quirk is the ability to copy other peoples powers. Neito is impressed that even an idiot like Katsuki could figure it out. When Katsuki tries to attack again, Neito's classmate: Kojiro Bonto uses his Quirk to immobilize Team Bakugo.
As other teams close in, Team Monoma decides to leave the area, but not before Neito taunts Katsuki about saying that he was going to win during the festival's opening ceremony. As time runs low, Neito plans to allow the clock to run out and secure second place. However, Katsuki suddenly flies at them using an explosion. Neito orders Kosei to stop Katsuki using his Solid Air Quirk, but the latter punches through it and snags two of their headbands. Other teams try to capitalize on Team Monoma, but Neito uses Kosei's Quirk to repel them. With only one headband remaining, Kosei states that the team is in fourth and Neito agrees to settle for last qualifying spot. However, his Class 1-A rival does the exact opposite.Katsuki strategically uses his teammates Quirks to close the distance between the two teams. Kosei tries to stop him, but Katsuki blasts through the air shield and takes Neito's last headband. The Cavalry Battle ends, and without any points Team Monoma fails to advance to the finals. 
Having been eliminated from the primary competition, Neito reluctantly participates in the recreational activities provided prior to the final round. He takes notice of all the Class 1-A students doing their best in the activities, and insults them for taking the recreational games too seriously.
During the scavenger hunt, Itsuka Kendo turns Neito in since she needs a "perverse person". Neito says that she may have the wrong impression of him, but she disagrees.When Ibara Shiozaki easily defeats Denki Kaminari, Neito taunts Class 1-A, then Itsuke stops him and apologizes for his behavior. Five fights later, Neito Monoma pays close attention to the duel between Katsuki and Ochaco Uraraka. He notices Ochaco's strategy long before many of the other viewers, and even comments that some of them need to look closer at the battle. When Ochaco makes her move, Neito explains her plan of action to everyone. After Katsuki defeats Fumikage Tokoyami in the semi-finals, Itsuka teases Neito by saying that he chose a scary person to make an enemy out of. Neito retorts that Katsuki was just lucky his Quirk so well in that match up. In the Sports Festival's closing ceremony Neito joins his class in honoring the first, second and third place winners.
Just prior to the end of their first term, Neito confronts Class 1-A in the lunchroom. He bumps into Izuku's head purposely and asks him about his encounter with the Hero Killer: Stain. Neito claims that Class 1-A's popularity is based solely on their poor luck and goes on to say that they may bring misfortune onto his class as well. Itsuka steps in and knocks Neito out with a single chop. He wakes while she's discussing the final exams format with their rivals. Neito berates her for sharing information, but she knocks him out again and drags his unconscious body away.
When the first semester of U.A. ends and the summer break begins. On the day of the forest lodge trip, when Neito finds out about some of Class 1-A needing supplementary lessons. He mocks Class 1-A for their failures until Itsuka Kendo appears and hits him on the neck.
When Class 1-B arrives at the training camp, their homeroom teacher Sekijirou Kan explains that they will be extending their Quirks and that the more they use their Quirks, the stronger they will be by breaking their limits.
Quirk and Abilities
Copy (コピー Kopī?): Neito's Quirk allows him to duplicate and use another Quirk after coming into contact with the Quirk user. After doing so, Neito gains full access to the Quirk he has copied and can use it however he likes. This Quirk also allows him to copy multiple Quirks. However, a drawback is that Neito can only use the Quirk he has copied for five minutes, and after the five minutes are over, he loses access to that Quirk. Also, Neito cannot simultaneously use two or more copied Quirks at the same time.
Intellect: He is shown to be very intelligent, as he was able to see through Uraraka's true strategy during her fight against Bakugo, something many pro heroes present were unable to do. He also formulated a strategy for Class 1-B during the first stage of the Sports Festival, by which the Class 1-B students were supposed to purposely place low in order to make Class 1-A underestimate them.
Neito sees Katsuki, along with the other members of his class, as arrogant, and their popularity must be toppled. However, Katsuki didn't give him much attention until he took his bandana and mocked him for being attacked by villains every year. This alone enraged Katsuki so much to the point of overlooking Izuku, whom he had his eyes on, in order to destroy Neito's team first. Later, after repeated taunting, mocking and copying of his Quirk, Katsuki's rage just grew even further and he swore again that he will become number 1, but this time he adds that he will be destroying everyone. Neito also thinks that Katsuki is a war criminal.
Neito and Itsuka are in the same class. She seems to have the habit of keeping him in check, as she told him to stop provoking Katsuki and stopped him from picking a fight with Izuku.
Monoma and Tetsutetsu are on good terms as classmates. Tetsutetsu also trusts Monoma's judgement with Tetsutetsu along with most of Class 1-B following his plan to rank in the lower end of the Obstacle Course in the UA Sports Festival and during the Cavalry Battle working together (to no avail) to target Class 1-A's members. During the Cavalry Battle's start the two also promised to not hold grudges against either regardless of the final result of the game.
- Neito's name comes from "物真似" (monomane?), meaning "mimicry". Additionally, "物間" (monoma?) means "among things". "寧" (nei?) means "repose, serenity, peace, peaceful", and "人" (hito?) means "person".
- Neito likes French cuisine and Franco-Belgian comics.
- Neito is based on a real person, according to Horikoshi.
- Despite having a 5/5 Intelligence Stat, Neito did not pass the End of Year Exam.
- (To his classmates) "Class A thinks it's so great. Well, let's show 'em... why we in Class B hung back and placed low in the preliminaries."